The EUREF (Reference Frame Sub-Commission for Europe) Permanent GNSS Network (EPN) serves as the backbone for the realization of, and access to, the European Terrestrial Reference System (ETRS89). The cumulative site positions and velocities for the EPN stations are used for national ETRS89 densifications and geo-information applications. EUREF has developed specific guidelines through which European countries ask validation of their national ETRS89 densification campaigns. Today, the majority of the European countries has passed this process and a large part of European National Mapping and Cartographic Agencies have officially adopted ETRS89. In addition, ETRS89 plays a fundamental role in INSPIRE (Infrastructure for Spatial Information in the European Community).